Chiral Symmetry Breaking in Gold Stellated Nanoicosahedrons

The integration of high-order symmetry with chiral geometry on individual nanoparticles is intriguing and would provide exciting insights into the chirality transfer from molecules to bulk materials; however, it remains a challenge yet to be addressed. Here we report the synthesis of chiral stellated nanoicosahedrons (SNIs), starting from Au nanoicosahedrons with a high-order (I_h) symmetry. A chirality transfer strategy based on the synergistic manner of glutathione and copper ions was employed to drive the chiral symmetry breaking in Au SNIs. Chiral Au SNIs with the I point group display highly twisted edges with 532 rotational symmetry and remarkably high chiroptical responses. Benefiting from the highly stellated geometry and intrinsic plasmonic characteristics, chiral Au SNIs also exhibit superior single-particle chiroptical and surface-enhanced Raman scattering properties, which hold great significance for applications in sensing and photonics. Our work provides an important knowledge framework that guides the synthesis of chiral materials with increasing architectural diversity toward chirality-dependent applications.